From 8b54c314863e7e9861470844e09c0453800748ae Mon Sep 17 00:00:00 2001 From: Daniel Black Date: Wed, 14 Mar 2018 13:31:28 +1100 Subject: [PATCH] MDEV-8743: where O_CLOEXEC is available, use for innodb buf_dump As this is the only moderately critical fopened for writing file, create an alternate path to use open and fdopen for non-glibc platforms that support O_CLOEXEC (BSDs). Tested on Linux (by modifing the GLIBC defination) to take this alternate path: $ cd /proc/23874 $ more fdinfo/71 pos: 0 flags: 02100001 mnt_id: 24 $ ls -la fd/71 l-wx------. 1 dan dan 64 Mar 14 13:30 fd/71 -> /dev/shm/var_auto_i7rl/mysqld.1/data/ib_buffer_pool.incomplete --- include/my_global.h | 5 +++++ storage/innobase/buf/buf0dump.cc | 15 ++++++++++++++- storage/xtradb/buf/buf0dump.cc | 15 ++++++++++++++- 3 files changed, 33 insertions(+), 2 deletions(-) diff --git a/include/my_global.h b/include/my_global.h index 5ea761d587e..ad1527d7b37 100644 --- a/include/my_global.h +++ b/include/my_global.h @@ -601,6 +601,11 @@ typedef SOCKET_SIZE_TYPE size_socket; #ifndef O_CLOEXEC #define O_CLOEXEC 0 #endif +#ifdef __GLIBC__ +#define STR_O_CLOEXEC "e" +#else +#define STR_O_CLOEXEC "" +#endif #ifndef SOCK_CLOEXEC #define SOCK_CLOEXEC 0 #endif diff --git a/storage/innobase/buf/buf0dump.cc b/storage/innobase/buf/buf0dump.cc index 5d5be0505f6..306dcc2ec18 100644 --- a/storage/innobase/buf/buf0dump.cc +++ b/storage/innobase/buf/buf0dump.cc @@ -220,7 +220,20 @@ buf_dump( buf_dump_status(STATUS_NOTICE, "Dumping buffer pool(s) to %s", full_filename); - f = fopen(tmp_filename, "w"); +#if defined(__GLIBC__) || defined(__WIN__) || O_CLOEXEC == 0 + f = fopen(tmp_filename, "w" STR_O_CLOEXEC); +#else + { + int fd; + fd = open(tmp_filename, O_CREAT | O_TRUNC | O_CLOEXEC | O_WRONLY, 0640); + if (fd >= 0) { + f = fdopen(fd, "w"); + } + else { + f = NULL; + } + } +#endif if (f == NULL) { buf_dump_status(STATUS_ERR, "Cannot open '%s' for writing: %s", diff --git a/storage/xtradb/buf/buf0dump.cc b/storage/xtradb/buf/buf0dump.cc index 09ac460f865..0bc222d2cc2 100644 --- a/storage/xtradb/buf/buf0dump.cc +++ b/storage/xtradb/buf/buf0dump.cc @@ -220,7 +220,20 @@ buf_dump( buf_dump_status(STATUS_NOTICE, "Dumping buffer pool(s) to %s", full_filename); - f = fopen(tmp_filename, "w"); +#if defined(__GLIBC__) || defined(__WIN__) || O_CLOEXEC == 0 + f = fopen(tmp_filename, "w" STR_O_CLOEXEC); +#else + { + int fd; + fd = open(tmp_filename, O_CREAT | O_TRUNC | O_CLOEXEC | O_WRONLY, 0640); + if (fd >= 0) { + f = fdopen(fd, "w"); + } + else { + f = NULL; + } + } +#endif if (f == NULL) { buf_dump_status(STATUS_ERR, "Cannot open '%s' for writing: %s",